package com.coinworld.utils;

import org.springframework.web.multipart.MultipartFile;
import sun.misc.BASE64Decoder;

import java.io.*;

/**
 * @description
 * @author:
 * @create: 2019-08-08 14:44
 **/
public class Base64DecodeMultipartFile implements MultipartFile{

    private final byte[] imgContent;

    private final String header;


    public Base64DecodeMultipartFile(byte[] imgContent, String header) {
        this.imgContent = imgContent;
        this.header = header.split(";")[0];
    }


    @Override
    public String getName() {
        return System.currentTimeMillis() + Math.random() + "." + header.split("/")[1];
    }


    @Override
    public String getOriginalFilename() {
        return System.currentTimeMillis() + (int) Math.random() * 10000 + "." + header.split("/")[1];
    }


    @Override
    public String getContentType() {
        return header.split(":")[1];
    }


    @Override
    public boolean isEmpty() {
        return imgContent == null || imgContent.length == 0;
    }


    @Override
    public long getSize() {
        return imgContent.length;
    }


    @Override
    public byte[] getBytes() throws IOException {
        return imgContent;
    }


    @Override
    public InputStream getInputStream() throws IOException {
        return new ByteArrayInputStream(imgContent);
    }


    @Override
    public void transferTo(File dest) throws IOException, IllegalStateException {
        new FileOutputStream(dest).write(imgContent);
    }

    /**
     *      * base64转multipartFile
     *      *
     *      * @param base64
     *      * @return
     *      
     */
    public static MultipartFile base64Convert(String base64) {
        String[] baseStrs = base64.split(",");
        BASE64Decoder decoder = new BASE64Decoder();
        byte[] b = new byte[0];
        try {
            b = decoder.decodeBuffer(baseStrs[1]);
        } catch (IOException e) {
            e.printStackTrace();
        }
        for (int i = 0; i < b.length; ++i) {
            if (b[i] < 0) {
                b[i] += 256;
            }
        }
        return new Base64DecodeMultipartFile(b, baseStrs[0]);
    }

    /**
     * MultipartFile 转 File
     * @param file
     * @throws Exception
     */
    public static File multipartFileToFile(MultipartFile file ,String fileName,String path) throws Exception {

        File toFile = null;
        if (file.equals("") || file.getSize() <= 0) {
            file = null;
        } else {
            InputStream ins = null;
            ins = file.getInputStream();
            File fileDir = new File(path);
            if (!fileDir.exists()) {
                fileDir.mkdirs();
            }
            toFile = new File(path+fileName);
            inputStreamToFile(ins, toFile);
            ins.close();
        }
        return toFile;
    }
    public static void inputStreamToFile(InputStream ins, File file) {
        try {
            OutputStream os = new FileOutputStream(file);
            int bytesRead = 0;
            byte[] buffer = new byte[8192];
            while ((bytesRead = ins.read(buffer, 0, 8192)) != -1) {
                os.write(buffer, 0, bytesRead);
            }
            os.close();
            ins.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
